Technical Field
The present invention relates to a package substrate; especially relates to a package substrate having a glass fiber layer embedded therein.
Description of Related Art
FIG. 1 shows a prior art U.S. Pat. No. 9,263,373.
FIG. 1 shows a prior art. U.S. Pat. No. 9,263,373 disclosed a package substrate comprises a first redistribution layer RDL1, a second redistribution layer RDL2, and a third redistribution layer RDL3. Since the high density film is very thin roughly 50-200 um in total thickness, in order to enhance the stiffness or mechanical strength of the high density film for easy handling, fiber-based filler 55 can be embedded in one of the dielectric layer or molding compound to reinforce the strength of the high density film according to the present invention. The first redistribution layer RDL1 has a plurality of bottom metal pads B01 and a plurality of top metal pads B02. The third redistribution layer RDL3 has a plurality of bottom metal pads T01 and a plurality of top metal pads T02. The fiber-based filler 55 is embedded in the third redistribution layer TDL3. The top side of the package substrate is PCB side, and a bottom side of the package substrate is a chip side. A nanochip 60 is configured on bottom side of the package substrate.
The prior art did not disclose detailed relationship and structure for the fiber-based filler 55 within the third redistribution layer RDL3. A more feasible embodiment needs to be made so that the thin film package substrate can be easily handled for chip or chips to mount thereon.